The latest Paper of the Month for Parasitology is “Immunochemotherapy for visceral leishmaniasis: combinatorial action of Miltefosine plus LBSapMPL vaccine improves adaptative Th1 immune response with control of splenic parasitism in experimental hamster model” and is freely available for one month. 

Visceral Leishmaniasis (VL) is considered one of the most important neglected diseases worldwide. One of the major obstacles in the fight against it, is the absence of effective prophylactic measures (vaccines) and the scarcity of therapeutic strategies to control the disease. In this context, due to the limited therapeutic arsenal available to treat the VL, many people die during treatment because the available drugs are quite toxic. In addition, the most effective drugs and those that are better tolerated by patients are very expensive and lead to the collapse of the public health system in the poorest regions.

Thus, in the past decade, our research group here in Brazil, at the Federal University of Ouro Preto – UFOP, has been working tirelessly to develop new treatment strategies for VL, aiming to reduce costs and toxicity, improving acceptability treatment, and also preventing the emergence of parasite resistant strains to available drugs.

Therefore, we tried to use vaccine therapy as a tool capable of promoting the activation of the host’s immune system which could be combined with chemotherapy to control the infection by the Leishmania infantum parasite. So, we combine a vaccine, developed by our research group using small pieces of the parasite (L. braziliensis), to induce a quick and effective immunological response concomitantly with a direct drug action (Miltefosine). In the lab, we used a susceptible experimental model for VL study, the hamster Mesocricetus auratus, and we performed the treatment of Leishmania-infected animals using the combination of therapies (vaccine plus Miltefosine – immunochemotherapy) and we observed fantastic results people! In blood, we observed restoration of hematological and biochemical parameters, and improvement of immunity with control of parasitism in target organs of the disease like spleen. These results demonstrate that the immunochemotherapy protocol can stimulate the immune system, inducing an expressive cellular response sufficient to control the parasites in the spleen, standing out as a promising proposal for the VL treatment.

Our data suggest that using a half course of Miltefosine associated with our vaccine therapy has the same or an even better effect compared to conventional therapy (only chemotherapy). Hence, we believe that the use of this type of therapy can bring numerous benefits to the patient, such as reduced toxicity, reduced costs and reduced treatment time, creating an important therapeutic perspective for the Visceral Leishmaniasis patients around the world.

The paper “Immunochemotherapy for visceral leishmaniasis: combinatorial action of Miltefosine plus LBSapMPL vaccine improves adaptative Th1 immune response with control of splenic parasitism in experimental hamster model” by Lívia M. Carvalho and Bruno M. Roatt, published in Parasitology, is available free for a month.